The present invention discloses a fruit and vegetable crisp slice production method by using microwave assisted pressure-difference flash evaporation and drying, comprising the following steps: (1) fruits and vegetables are sorted, washed, peeled, pitted and sliced to obtain fruit and vegetable slices; (2) the fruit and vegetable slices are subjected to pretreatment; (3) the pretreated fruit and vegetable slices are placed into a puffing cabin to conduct microwave assisted vacuum pre-driying; (4) the pre-dried semi-dried fruit and vegetable slices are subjected to microwave assisted pressure-difference flash evaporation and drying; and (5) the puffed fruit and vegetable slices are subjected to microwave assisted vacuum drying and the fruit and vegetable slices are dried to a final moisture content. The fruit and vegetable crisp slice has the following advantages: the drying efficiency of the fruit and vegetable slices is significantly shortened and the puffing degree and crispness of the fruit and vegetable slices are significantly improved. At the same time, the color and luster, and the nutrients of the raw materials are maintained. In addition, the production devices are mature and the production technology is simple. The present invention also provides the fruit and vegetable crisp slices and a fruit and vegetable powder using the fruit and vegetable crisp slices as raw materials.